PTFE coatings on the “U” bolts normally come as an inner lining on the rubber sleeve. This is done where low coefficient of friction and anti-stick properties is required on the pipe installation. Polytetrafluoroethylene (PTFE), is a thermoplastic member of the fluoropolymer family of plastics. PTFE has a low coefficient of friction, excellent insulating properties, and is chemically inert to most substances. It also can withstand high heat applications and it is well know for its anti-stick properties.